1. Field of the invention:
This invention relates to torque control for the automatic shut-off of pneumatically powered handheld tools.
2. Description of the Prior Art:
A type of tool having automatically operable shut-off means is found in U.S. Pat. No. 3,667,345, which tool incorporates a pneumatically balanced air flow control valve. Another type, using a centrifugally responsive ball valve, is disclosed in U.S. Pat. No. 3,850,553. A tool using a push rod operable at a predetermined torque to close an air inlet valve in response to a ball which is forced up a cam ramp when the predetermined torque is realized can be found in U.S. Pat. No. 4,071,092.